The present invention relates to the structure of the casing of a radio communication apparatus or similar apparatus which is powered by, for example, a dry battery. More particularly, the present invention is concerned with a structure for preventing a battery cover, which is removable from the casing of a radio pager or similar radio communication apparatus for the replacement of a battery, from accidentally coming off the casing.
A radio pager is extensively used today and usually powered by a dry battery having a limited life. The user of the pager, therefore, has to replace the battery when it dies. For the replacement of the battery, part of the casing of the pager comprises a battery cover which can be readily attached to and detached from the casing. Various structures have heretofore been proposed for attaching and detaching the battery cover from the casing. For example, the casing and the battery cover may be provided with respective guide rails and slidably engaged with each other. This kind of conventional structure has a locking mechanism for preventing the battery cover from slipping out of the casing in the sliding direction. Specifically, when the battery cover is attached to the casing, a lug extending out from one end of the battery cover mates with a recess formed in the casing.
The above-described anti-fall structure has a problem in that as the battery cover is repetitively attached to and detached from the casing, the locking engagement of the lug and recess becomes loose due to wear and the battery cover can easily fall off the casing. Moreover, since this type of receiver is transported and operated in severe conditions, the battery cover is apt to come off due to shocks and impacts. Then, the battery would spring out of the casing or the battery cover itself would be lost.
In light of the above, improved anti-fall structures for a radio communication apparatus or similar apparatus are taught in, for example, Japanese Utility Model Laid-Open Publication Nos. 11720/1990 and 11721/1990. The improved anti-fall structures each includes a locking mechanism for preventing the battery cover from easily coming off the casing and has obtained satisfactory results. The anti-fall structure of the present invention constitutes a further improvement over such conventional structures.